Spark plug



Jan. 8 1924.

H. MACKEY SPARK PLUG Filed Feb. 27, 1923 Patented Jan. 8, 1924.

UNITED STATES HENRY mcirnyyor Penna, IOWA.

SPARK PLUG.

Application iiled February 27, 1923. Serial No. 621,620.

To all whom it may concern. v

Be it known that I, HENRY MACKEY, a citizen of the United States of America, and resident of Fonda, in thecounty of Pocahontas and State of Iowa, have inventedcertain new and useful Improvements in Spark-Plugs, of which the following is a specification.

This invention relates to spark plugs for internal combustion motors, and an object of the invention is to produce a spark plug which has a solid bottom or inner end, and of a construction that renders it impossible for oil to become deposited on the inner end, and it-also is of such a construction as to be free of corrosion or a deposit of carbon which might tend to foul the plug.

A further object of this invention is to produce a spark plug in which there is no chamber in the inner end for the accumulation of substances which might tend to short circuit the current.

It is a further object of this invention to produce a spark plug in which the electrode is insulated from the body of the plug without the use of porcelain so that there is no likelihood of fracture which would permit a short circuit to develop; and furthermore, the insulating material may be renewed, should it become impaired in any way, at a comparatively small cost, so that a spark plug will not be a total loss, even though a short circuit develops, as the parts thereof may be dismantle-d for the purpose of renewing the impaired parts.

A still further object of this invention is to produce a plug the proportions of which may be varied to suit particular requirements as to the size of the motor with which it is to operate, and the inventor does not wish to be limited with respect to the proportions.

With the foregoing and other objects in view, the invention consists in the details of construction, and in the arrangement and combination of parts to be hereinafter more fully set forth and claimed.

In describing the invention in detail, reference will be had to the accompanying drawings forming part of this application wherein like characters denote corresponding parts in the several views, and in which Figure 1 illustrates a View in elevation of a spark plug embodying the invention;

better results than other dimensions, it is obvious that the thickness of the insulation may be changed to suit particular require ments, and the diameter of the electrode may be changed in like manner.

The ends of the body have recesses!) and 10 respectively, of larger diameter than the central bore or aperture, and the electrode has an enlarged portion 11 fitting in the seat 10. An insulating sleeve 12 is interposed between the periphery of the enlarged-portion and the wall of the recess, and a ring insulator 13 is interposed between the insulators 6 and 12, and the said ring insulator rests on the shoulder 14 formed at the junction of the electrode and the enlargement 12 thereof. The insulator terminates in a tapered stem 15 with relation to which a grounding terminal 16 is adustable, it being understood that the grounding terminal is pliable to an extent that it is and may be adjusted with relation to the stem.

An insulating washer 17 fits against the inner end of the body and protects the joint between the insulation 12 and the wall of the body against the accumulation of material that might foul or short circuit the plug. The stem is further provided with a flange 18 which bears against the washer or insulator 17 and forces it into engagement with the end of the body, as will presently appear.

The recess 9 has an insulating washer 19 bearing against its bottom wall and against the end of the insulating sleeve 8, the said insulator 19 being held in place by a nut 20 that engages the threaded portion 21 of the electrode.

A washer 22 is applied to the outer end of the electrode and it bears against the outer end of the body of the spark plug. It is held in place by a nut 23 that is threaded on the electrode and bears against a lock washer 24 that serves to prevent the nut 23 from backing. The nut 23 when forced into engagement with the Washer results in pulling the flange 18 in contact with the insulator 17, thus effecting a tight joint at and protecting the inner end of the spark plug.

The usual binding nut 25 may be threaded on the outer end of the valve stem to clamp the terminal against the nut 23, or such other appropriate anchorage for the terminal may be employed as is desirable in practice. 7

The objects of the invention having been stated, it is believed that the construction and operation will be understood from the foregoing description.

I claim:

1. In a spark plug, a body of soft metal, an electrode extending therethrough having an enlargement near its inner end, the said electrode terminating in a stem, a flange at the junction of the stem and the enlarged portion of the electrode, an insulating sleeve interposed between the electrode and the wall of the body, the said body having recesses in its inner and outer ends, the first mentioned recess constituting a seat for the enlarged portion of the electrode, an insulating sleeve interposed between the enlarged portion of the electrode and the wall of the body, an insulating ring interposed between the ends of the first and second mentioned insulators at the junction of the electrode and. the enlarged portion thereof, an insulator interposed between the flange and the end of the body, an insulating ring applied to the electrode at the outer end and resting against the wall of the recess in engagement with the outer end of the first mentioned insulator, and means for retaining the parts in assembled relation.

2. In a spark plug, a body of soft metal, an electrode extending therethrough having an enlargement near its inner end, the said electrode terminating in a stem, a flange at the junction of the stem and the enlarged portion of the electrode, an insulating sleeve interposed between the electrode and the wall of the body, the said body having recesses in its inner and outer ends, the first mentioned recess constituting a seat for the enlarged portion of the electrode, an insulating sleeve interposed between the enlarged portion of the electrode and the wall of the body, an insulating ring interposed between the ends of the first and second mentioned insulators at the junction of the electrode and the enlarged portion thereof, an insulator interposed between the flange and. the end of the body, an insulating ring applied to the electrode at the outer end and resting against the wall of the recess in engagement with the outer end of the first mentioned insulator, a nut threaded on the outer end of the electrode bearing against the insulating disk, a plate applied to the electrode and bearing against the outer end of the said body, and means for retaining the parts in assembled relation to one another.

7 HENRY MAOKEY. 

